LM2841YMK-ADJL - 300mA 42V Buck Converter | Texas Instruments
Teilenummer: LM2841YMK-ADJL ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $2.1 | $2,10 |
| 10 | $1.84 | $18,40 |
| 100 | $1.52 | $152,00 |
| 500 | $1.28 | $640,00 |
| 1.000 | $1.08 | $1.080,00 |
LM2841YMK-ADJL Übersicht
What is a buck converter? A buck converter (step-down DC/DC switching regulator) is a power management device that uses an internal MOSFET switch, an inductor, and a capacitor network to convert a higher DC input voltage to a lower regulated DC output voltage with high efficiency. Buck converters sit in the power management taxonomy as: buck converter -> DC/DC switching regulator -> voltage regulator -> power management IC. They are preferred for higher step-down ratios where linear regulators (LDOs) waste excessive power as heat.
Key features include a 4.5 V to 42 V wide input range that tolerates automotive load-dump conditions and 24 V industrial buses, internal compensation that eliminates most external compensation components, and built-in cycle-by-cycle current limit, thermal shutdown, and soft-start on the same enabling reference family. The thin SOT-23-6 footprint occupies approximately 9 mm² of board space, suiting space-constrained point-of-load applications.
Architecturally, the device uses a fixed-frequency peak-current-mode control topology. The internal high-side switch commutates the inductor at 1.5 MHz, and the feedback loop regulates the output against the 0.765 V internal reference using an external resistor divider. The peak-current-mode control provides inherent cycle-by-cycle current limiting and simplifies loop compensation. Operating junction temperature spans -40 C to +125 C, supporting automotive and industrial environments.
Typical applications include point-of-load regulation for 24 V industrial buses, powering microcontrollers and sensors from unregulated 12 V or 18 V sources, portable and battery-powered systems, LED constant-current drivers, and automotive infotainment and body electronics. The wide input range also supports wall-transformer-fed consumer electronics, telecom point-of-load rails, and distributed supply architectures.
When designing with this regulator, ensure the input capacitor and bootstrap capacitor are placed close to the IC pins and that the inductor is sized for 1500 kHz operation (typically 4.7 uH to 22 uH). Calculate power dissipation by (I_OUT × V_DIODE) for the rectifying path and (I_OUT × VIN × (1 - VOUT/VIN)) for the high-side switch, then verify thermal margin against the 31.6 C/W theta_JA in TSOT-23.
This page synthesizes distributor stock and pricing, drop-in alternatives across TI and competing brands, and practical PCB/thermal design notes not found in the bare datasheet.
Drop-in-Alternativen für LM2841YMK-ADJL – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit LM2841YMK-ADJL (gleiche Bauform und Footprint) – abweichend in Input Voltage Range, Maximum Output Current, Output Voltage Range, Package, Switching Frequency.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
LM2841YMKX-ADJL/NOPB
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2841XMK-ADJL/NOPB
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2841YMK-ADJL/Q1
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2841XMK-ADJL/Q1
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2840YMK-ADJL/NOPB
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2842YMK-ADJL/NOPB
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
LM2841YMK-ADJL Grenzwerte & elektrische Eigenschaften
| Topologie | Step-Down (Buck) DC/DC Switching Regulator |
| Eingangsspannungsbereich | 4.5 V to 42 V |
| Ausgangsspannungsbereich | 0.765 V to 33 V (Adjustable) |
| Maximaler Ausgangsstrom | 300 mA |
| Referenzspannung | 0.765 V |
| Schaltfrequenz | 1500 kHz (nominal) |
| Internal Switch RDS(ON) | 0.9 ohm (typical) |
| Typical Efficiency | 85 percent |
| Control Topology | Peak Current-Mode PWM |
| Betriebstemperaturbereich | -40 C to +125 C |
| Gehäuse | TSOT-23-6 (DDC, Thin SOT-23-6, 6 pins) |
| Montageart | Surface Mount |
| MSL-Level | 1 (per TI SOT-23 family, infinite floor life) |
| RoHS-Status | Compliant |
| Lead-Free | Yes (NOPB suffix) |
LM2841YMK-ADJL Pin-Konfiguration
| Pin 1 | SW — Switch node - connects to external inductor and rectifier |
| Pin 2 | GND — Ground reference |
| Pin 3 | FB — Feedback input - external resistor divider sets VOUT to 0.765 V reference |
| Pin 4 | EN — Enable input (active-high); tie to VIN if not used |
| Pin 5 | VIN — Input supply voltage, 4.5 V to 42 V; decouple with 100 nF + 1 uF ceramic |
| Pin 6 | BST — Bootstrap capacitor (100 nF) to SW for high-side gate drive |
Typische Anwendungen
LM2841YMK-ADJL ist geeignet für 7 Anwendungs: Industrial 24V Point-of-Load, Automotive 12V Body Electronics, Portable Battery-Powered Systems, LED Constant-Current Driver, Distributed Telecom 48V Bus, Wall-Adapter Consumer Power, Sensor Module Power Conditioning.
Industrial 24V Point-of-Load
The LM2841YMK-ADJL's 4.5V to 42V input range directly accepts unregulated 24V industrial bus rails without pre-regulation, while its 300 mA output can power microcontrollers, sensors, and op-amps from a single TSOT-23-6 footprint of approximately 9 mm². At VIN=24V and VOUT=3.3V/200mA typical load, the 1.5 MHz peak-current-mode control provides stable regulation with 10 uH inductor and 22 uF ceramic output. Unlike a linear LDO that would dissipate (24-3.3)*0.2=4.1W of heat, the LM2841 stays under 1W package dissipation. The 42V abs-max input tolerates 24V bus transients above nominal industrial ratings. Use a 100 nF VIN bypass and 100 nF BST bootstrap capacitor for stable operation.
Empfohlen
Automotive 12V Body Electronics
The LM2841YMK-ADJL-Q1 (AEC-Q100 Grade 1 qualified) operates from a 4.5-42V automotive rail that absorbs double-battery jump (24V) and load-dump transients up to 42V, making it ideal for body electronics modules and infotainment subsystems. The 300 mA output powers CAN transceivers, sensor clusters, and LED drivers. Operating junction temperature spans -40C to +125C and the TSOT-23-6 footprint survives under-hood thermal stress. Compared to a discrete buck using a 555 timer + MOSFET, the integrated LM2841 reduces BOM by ~10 parts and provides internal soft-start plus cycle-by-cycle current limit. The 1.5 MHz switching frequency keeps AM band interference out and is placed near the audio band but well above 1.5 MHz.
Empfohlen
Portable Battery-Powered Systems
The LM2841YMK-ADJL is well-suited for portable systems powered by 2S to 4S Li-ion packs or 6V to 18V wall adapters, where its 4.5-42V input accommodates battery voltage variation and its 300 mA output drives small microcontrollers, BLE radios, and sensor hubs. At VIN=8.4V (full 2S Li-ion) and VOUT=3.3V/150mA, efficiency reaches ~85% peak per the LM2841 datasheet typical characteristics. Quiescent current of ~1 mA in switching operation keeps sleep current manageable for an integrated limiter; for true nanoampere sleep, a separate nano-Iq LDO is recommended. Compared to a discrete buck the integrated regulator reduces standby drain and PCB area to a 9 mm² TSOT-23-6 footprint.
Empfohlen
LED Constant-Current Driver
The LM2841YMK-ADJL configured in constant-current mode using a sense resistor in series with the drain bridge provides up to 300 mA of regulated current for high-brightness LEDs in automotive interior lighting, signage, and architectural lighting. The 1.5 MHz switching frequency is well above the audible band, eliminating inductor whine. The 42V input tolerates 24V commercial LED driver rails without pre-regulation. Internal cycle-by-cycle current limiting adds safety against LED shorts. Compared to a linear LED driver that would dissipate (VIN-VIN) × ILED as heat, the LM2841 switching approach dissipates under 0.5W for the same LED current. Use a 10 uH inductor and 10 uF ceramic output for low-ripple LED current.
Empfohlen
Distributed Telecom 48V Bus
The LM2841YMK-ADJL accepts the standard telecom 48V bus after a small pre-transistor or wide-VIN front end, providing an isolated/non-isolated point-of-load step-down to 3.3V or 5V rails for logic, FPGAs, and DSPs. The 42V maximum input is suitable for nominal 36V telecom intermediate buses. At VIN=36V and VOUT=3.3V/200mA typical load the converter operates at ~80% efficiency. The TSOT-23-6 footprint with internal compensation reduces the loop area to ~9 mm², supporting distributed supply architectures where many point-of-load rails share a backplane. Compared to a brick building from 48V down, the LM2841 drops the converter to chip-scale.
Empfohlen
Wall-Adapter Consumer Power
The LM2841YMK-ADJL operates from wall-adapter outputs ranging from 5V USB up to 30V unregulated DC adapters, regulating to 3.3V, 5V, or 12V rails for set-top boxes, white goods, and home automation hubs. The wide 4.5-42V input tolerates adapter tolerance and load transients. At VIN=12V and VOUT=5V/250mA typical load the regulator maintains >85% efficiency, near 90% peak in the 100-200 mA range. The internal soft-start eliminates the inrush current spike that stresses the wall adapter. Compared to a linear regulator, the LM2841 wastes only ~1.7W at full load vs 7W wasted on a linear regulator. The TSOT-23-6 footprint is ideal for compact appliance designs.
Empfohlen
Sensor Module Power Conditioning
The LM2841YMK-ADJL conditions power from unregulated 12V or 24V sensor supply rails to clean 3.3V or 5V rails for analog and digital sensors in industrial measurement and process control applications. The 300 mA output powers multi-sensor modules including pressure, temperature, and flow sensors simultaneously. The 1.5 MHz switching frequency is far above sensor signal bandwidths, simplifying EMC compliance. Compared to a discrete buck the LM2841 reduces BOM count by ~10 components and shrinks PCB area to ~9 mm² for the regulator plus ~30 mm² for the LC filter. Internal thermal shutdown provides fault protection at high VIN and high IOUT combinations.
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Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für LM2841YMK-ADJL – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | LM2841YMKX-ADJL/NOPB | LM2841XMK-ADJL/NOPB | LM2841YMK-ADJL/Q1 | LM2840YMK-ADJL/NOPB | LM2842YMK-ADJL/NOPB |
|---|---|---|---|---|---|---|
| Package | TSOT-23-6 (DDC) | TSOT-23-6 (DDC) - same | TSOT-23-6 (DDC) - same | TSOT-23-6 (DDC) - same | TSOT-23-6 (DDC) - same | TSOT-23-6 (DDC) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Output Current (max) | 300 mA | 300 mA | 300 mA | 300 mA | 100 mA | 600 mA |
| Input Voltage Range | 4.5 V to 42 V | 4.5 V to 42 V | 4.5 V to 42 V | 4.5 V to 42 V | 4.5 V to 42 V | 4.5 V to 42 V |
| Switching Frequency | 1500 kHz | 1500 kHz | 1500 kHz | 1500 kHz | 1500 kHz | 1500 kHz |
| Reference Voltage | 0.765 V | 0.765 V | 0.765 V | 0.765 V | 0.765 V | 0.765 V |
| Internal Switch RDS(ON) | 0.9 ohm (typ) | 0.9 ohm (typ) | 0.9 ohm (typ) | 0.9 ohm (typ) | 1.6 ohm (typ) | 0.5 ohm (typ) |
| AEC-Q100 Qualified | No | No | No | Yes (Grade 1) | No | No |
| Operating Temperature Range | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C (AEC-Q100) | -40 C to +125 C | -40 C to +125 C |
| RoHS / Lead-Free | Yes (NOPB) | Yes (NOPB) | Yes (NOPB) | Yes | Yes (NOPB) | Yes (NOPB) |
Wichtigste Unterscheidungsmerkmale
- Highest current rating in 42V TSOT-23-6 family (vs. LM2840YMK-ADJL/NOPB)
- Smallest PCB footprint among 42V/300mA buck regulators (vs. LMR16006 (SOT-23-6 with different pinout))
- Automotive-grade option in same package (vs. LM2841YMK-ADJL/Q1)
- Lower RDS(ON) than smaller-current member (vs. LM2840YMK-ADJL/NOPB)
Designhinweise
Place input capacitor (1 uF to 10 uF ceramic) and bootstrap capacitor (100 nF) as close to the IC pins as possible. Keep the high-current loop (VIN - SW - L - COUT - GND) tight and minimize the SW node copper area to reduce EMI. The feedback resistor divider should connect directly to the output capacitor positive terminal with short traces to avoid pickup noise. Estimated: a tight 4-layer PCB layout reduces EMI by 6-10 dB compared to a loose 2-layer layout. Use a single ground plane and stitch vias around the switching loop.
Estimated: at VIN=24V, VOUT=3.3V, and IOUT=200mA, the LM2841 dissipates approximately (1 - 0.85) × (24 * 0.2) = 0.72 W. The TSOT-23-6 (DDC) package has a theta_JA of approximately 31.6 C/W on a standard JEDEC EIA-4118E test board, resulting in a junction temperature rise of ~22 C above ambient. At VIN=42V and IOUT=300mA full load, dissipation can reach ~1.5 W, requiring junction temperature derating. Reduce VIN-VOUT differential, lower IOUT, or improve PCB thermal copper area (top-layer pour plus thermal vias to inner layers) to maintain safe operation.
Do not exceed the absolute maximum VIN of 42V; add a TVS or Zener clamp for automotive load-dump protection. Ensure the bootstrap capacitor is in place and properly rated for 100 nF ceramic (X7R). Do not leave the EN pin floating - tie it to VIN or drive with a logic signal; otherwise the part may power up intermittently. The feedback divider resistors should be 1 percent or better to maintain output voltage accuracy. Use X7R (not Y5V) ceramic capacitors for the input and output to avoid DC bias derating. Estimated: a 10 uF Y5V cap at 5 V bias may drop to 2 uF effective, causing instability.
Switching frequency of 1500 kHz places the fundamental and harmonics above the AM broadcast band (530-1710 kHz) but below the 2.4 GHz Wi-Fi/Bluetooth band; EMI compliance with FCC Part 15 and EN 55022 requires filtering. Use a shielded inductor (not an unshielded drum core) to minimize radiated EMI. Add an input pi-filter (10 uF + ferrite bead + 10 uF) for conducted EMI suppression. Place the LM2841 switching node away from sensitive analog signal traces and avoid routing the SW node under other components. The TSOT-23-6 footprint aids EMI due to its small loop area compared to proper TI enclosures.
Compliance-Informationen
Standard LM2841YMK-ADJL is not AEC-Q100 qualified; choose LM2841YMK-ADJL/Q1 for automotive. RoHS compliant per TI product page. Lead-free per NOPB suffix. Halogen-free per TI product categorization data (MSL 1, Pb-free).
